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  <title>二进制安全字符串比较</title>
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  <div id="layout-content"><div id="function.strcmp" class="refentry">
 <div class="refnamediv">
  <h1 class="refname">strcmp</h1>
  <p class="verinfo">(PHP 4, PHP 5, PHP 7)</p><p class="refpurpose"><span class="refname">strcmp</span> &mdash; <span class="dc-title">二进制安全字符串比较</span></p>

 </div>
 
 <div class="refsect1 description" id="refsect1-function.strcmp-description">
  <h3 class="title">说明</h3>
  <div class="methodsynopsis dc-description">
   <span class="methodname"><strong>strcmp</strong></span>
    ( <span class="methodparam"><span class="type">string</span> <code class="parameter">$str1</code></span>
   , <span class="methodparam"><span class="type">string</span> <code class="parameter">$str2</code></span>
   ) : <span class="type">int</span></div>

  <p class="simpara">
   注意该比较区分大小写。
  </p>
 </div>


 <div class="refsect1 parameters" id="refsect1-function.strcmp-parameters">
  <h3 class="title">参数</h3>
  <p class="para">
   <dl>

    
     <dt>
<code class="parameter">str1</code></dt>

     <dd>

      <p class="para">
       第一个字符串。
      </p>
     </dd>

    
    
     <dt>
<code class="parameter">str2</code></dt>

     <dd>

      <p class="para">
       第二个字符串。
      </p>
     </dd>

    
   </dl>

  </p>
 </div>


 <div class="refsect1 returnvalues" id="refsect1-function.strcmp-returnvalues">
  <h3 class="title">返回值</h3>
  <p class="para">
   如果 <code class="parameter">str1</code> 小于
   <code class="parameter">str2</code> 返回 &lt; 0；
   如果 <code class="parameter">str1</code>
   大于 <code class="parameter">str2</code>
   返回 &gt; 0；如果两者相等，返回 0。
  </p>
 </div>


 <div class="refsect1 examples" id="refsect1-function.strcmp-examples">
  <h3 class="title">范例</h3>
  <p class="para">
   <div class="example" id="example-5963">
    <p><strong>Example #1 <span class="function"><strong>strcmp()</strong></span> 例子</strong></p>
    <div class="example-contents">
<div class="phpcode"><pre><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />$var1&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #DD0000">"Hello"</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">$var2&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #DD0000">"hello"</span><span style="color: #007700">;<br />if&nbsp;(</span><span style="color: #0000BB">strcmp</span><span style="color: #007700">(</span><span style="color: #0000BB">$var1</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">$var2</span><span style="color: #007700">)&nbsp;!==&nbsp;</span><span style="color: #0000BB">0</span><span style="color: #007700">)&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;echo&nbsp;</span><span style="color: #DD0000">'$var1&nbsp;is&nbsp;not&nbsp;equal&nbsp;to&nbsp;$var2&nbsp;in&nbsp;a&nbsp;case&nbsp;sensitive&nbsp;string&nbsp;comparison'</span><span style="color: #007700">;<br />}<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</pre></div>
    </div>

   </div>   
  </p>
 </div>

 
 <div class="refsect1 seealso" id="refsect1-function.strcmp-seealso">
  <h3 class="title">参见</h3>
  <p class="para">
   <ul class="simplelist">
    <li class="member"><span class="function"><a href="strcasecmp.html" class="function" rel="rdfs-seeAlso">strcasecmp()</a> - 二进制安全比较字符串（不区分大小写）</span></li>
    <li class="member"><span class="function"><a href="preg_match.html" class="function" rel="rdfs-seeAlso">preg_match()</a> - 执行匹配正则表达式</span></li>
    <li class="member"><span class="function"><a href="substr_compare.html" class="function" rel="rdfs-seeAlso">substr_compare()</a> - 二进制安全比较字符串（从偏移位置比较指定长度）</span></li>
    <li class="member"><span class="function"><a href="strncmp.html" class="function" rel="rdfs-seeAlso">strncmp()</a> - 二进制安全比较字符串开头的若干个字符</span></li>
    <li class="member"><span class="function"><a href="strstr.html" class="function" rel="rdfs-seeAlso">strstr()</a> - 查找字符串的首次出现</span></li>
    <li class="member"><span class="function"><a href="substr.html" class="function" rel="rdfs-seeAlso">substr()</a> - 返回字符串的子串</span></li>
   </ul>
  </p>
 </div>


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